Design, synthesis and biological evaluation of cyanopyridines, pyridopyrazolopyrimidines and pyridopyrazolotriazines as potential anticancer agents

Background: The continuous need for new anticancer drugs is a never-ending task due to cancer resistance to the existing drugs. Objective: This article aimed to Design, synthesis, characterization, and anticancer evaluation of cyanopyridines, pyridopyrazolopyrimidines and pyridopyrazolotriazines. Materials and Methods: FTIR spectra were recorded on Thermo nioclet iso10 FT-IR. 1H and 13C NMR spectra were recorded on on JEOL (500 MHz) and Bruker 400 MHz spectrometer. Anticancer activity was determined using MTT assay against three cancer cell lines namely liver cancer cell line (HepG-2), pancreatic cancer cell line (PANC-1), non-small lung cancer cell line (A-549) and normal fibroblast. Results and Discussion: New series of 3-cyanopyridines (2a,b, 4, 5, 9), pyridopyrimidine (10), pyridopyrazolopyrimidines (11a-c, 12a,b, 18), pyrazolopyridine salt (13) and pyridopyrazolotriazines (16a,b) were synthesized from 3-cyano-4,6- dimethyl-2-pyridone. The novel synthesized compounds were evaluated in vitro for their anticancer activity and their chemical structures were determined by elemental analysis and spectroscopic data. Conclusion: The obtained data revealed that some of the synthesized compounds showed remarkable anticancer activities, especially 11a exhibited superior potency to the reference drug cisplatin against A-549 (IC50 = 9.24 µg mL-1 compared by 11.76 µg mL-1 for reference drug) and safe (IC50 = 66 µg mL-1) for normal fibroblast. Furthermore, compound 16a displayed the highest activity among the tested compounds against HepG-2 (IC50 = 6.45 µg mL-1 equipotent to cisplatin) with the highest safety profile (IC50=113.97 µg mL-1).